CAPEC 描述
CAPEC 資訊
執行流程
[Find User Input] The adversary finds anywhere in the web application that uses user-supplied input in a form or action. This can also be found by looking at parameters in the URL in the navigation bar of the browser
[Add Duplicate Parameter Values] Once the adversary has identified what user input is used as HTTP parameters, they will add duplicates to each parameter one by one to observe the results. If the response from the HTTP request shows the duplicate parameter value concatenated with the original parameter value in some way, or simply just the duplicate parameter value, then HPP is possible.
- In the URL, add a duplicate parameter by using the "&" delimiter. For example "par1=val1" becomes "par1=val1&par1=val2". Depending on the backend API, this could be treated as "par1=val1, val2", which could lead to par1 being set to val2, ignoring val1.
- If the request is created based on user input directly on the page, the adversary will test by adding an encoded delimiter to the input. For example, the adverary might supply "1000%26action=withdraw" and the backend might interpret a POST request with the paramters "action=deposit&amount=1000&action=withdraw"
[Leverage HPP] Once the adversary has identified how the backend handles duplicate parameters, they will leverage this by polluting the paramters in a way that benefits them. In some cases, hardcoded parameters will be disregarded by the backend. In others, the adversary can bypass a WAF that might only check a parameter before it has been concatenated by the backend, resulting in malicious queries getting through.
前置條件
HTTP protocol is used with some GET/POST parameters passed所需資源
Any tool that enables intercepting and tampering with HTTP requests緩解措施
Configuration: If using a Web Application Firewall (WAF), filters should be carefully configured to detect abnormal HTTP requestsDesign: Perform URL encoding
Implementation: Use strict regular expressions in URL rewriting
Implementation: Beware of multiple occurrences of a parameter in a Query String
相關弱點
| 弱點名稱 | |
|---|---|
CWE-88 |
Improper Neutralization of Argument Delimiters in a Command The product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string. |
CWE-147 |
Improper Neutralization of Input Terminators The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as input terminators when they are sent to a downstream component. |
CWE-235 |
Improper Handling of Extra Parameters The product does not handle or incorrectly handles when the number of parameters, fields, or arguments with the same name exceeds the expected amount. |
參考資料
REF-397
HTTP Parameter PollutionLuca Carettoni, Stefano di Paola.
https://www.owasp.org/images/b/ba/AppsecEU09_CarettoniDiPaola_v0.8.pdf
REF-606
OWASP Web Security Testing Guidehttps://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/07-Input_Validation_Testing/04-Testing_for_HTTP_Parameter_Pollution.html
提交
| 名稱 | 機構 | 日期 | 發布日期 |
|---|---|---|---|
| CAPEC Content Team | The MITRE Corporation |
修改記錄
| 名稱 | 機構 | 日期 | 備註 |
|---|---|---|---|
| CAPEC Content Team | The MITRE Corporation | Updated Mitigations, References, Taxonomy_Mappings | |
| CAPEC Content Team | The MITRE Corporation | Updated Related_Attack_Patterns | |
| CAPEC Content Team | The MITRE Corporation | Updated Description, Execution_Flow |
